May 24, 2013

App Turns Your Smartphone Into A Mobile Mini Lab

Smartphones are increasingly becoming more beneficial as tools for uses other than what they were originally intended for. While people can still be found talking and texting more than ever, many have found that pushing a few buttons on their mobile devices helps them do much more than checking their e-mail or finding specific information over the Web.

Researchers have previously developed apps that turn your smartphone into a remote that can control everything from your TV to your alarm system. While there are particularly hundreds of other apps on the market that can do similar things, one development team has created an app that can turn your phone into a miniaturized mobile laboratory.

Researchers at the University of Illinois at Urbana-Champaign have developed a new cradle and app for the smartphone, specifically the iPhone, which uses the phone´s built-in camera and processing power as a biosensor to detect toxins, proteins, bacteria, viruses and other organisms.

Such a system could enable researchers to conduct on-the-spot tracking in the field, allowing for instant measurements of ground contamination, combine GPS and biosensing data to map the spread of pathogens, and even provide immediate medical diagnostic tests and food contaminant checks.

Study leader Brian Cunningham, a professor of electrical and computer engineering and bioengineering at U of I, said his team is interested in external biodetection methods — meaning tests that are not performed in the lab setting.

“Smartphones are making a big impact on our society — the way we get our information, the way we communicate. And they have really powerful computing capability and imaging. A lot of medical conditions might be monitored very inexpensively and non-invasively using mobile platforms like phones. They can detect molecular things, like pathogens, disease biomarkers or DNA, things that are currently only done in big diagnostic labs with lots of expense and large volumes of blood,” said Cunningham in a statement.

The cradle contains a series of smaller versions of the optical components found in much larger and more expensive lab devices. The wedge-shaped cradle holds the phone´s camera in alignment with the optical components. A photonic crystal at the heart of the biosensor acts like a mirror and only reflects one wavelength of light while the rest of the spectrum passes through. When biological matter attaches to the crystal, the reflected color will shift from a shorter wavelength to a longer one.

The iPhone biosensor also contains a normal microscope slide coated with photonic material. The slide is primed to react to a specific target molecule. The photonic crystal slide is inserted into a slot on the cradle and the spectrum measured. The reflecting wavelength shows up as a black gap in the spectrum. After exposure, the spectrum is re-measured. The degree of shift in the reflected wavelength then tells the app how much of the target molecule is a sample.

The test takes just a few minutes and the app can walk the user through the process step by step. Although the cradle only holds $200 worth of optical components, it is just as accurate as $50,000 models in the lab, making the device not only portable, but affordable and effective. The team notes it will work well for fieldwork, especially for researchers in developing nations who otherwise do not have the means to utilize expensive lab equipment.

In a paper published in the journal Lab on a Chip, the team demonstrated how the cradle and app work on an immune system protein. They maintained that the slide could be primed for any type of biological matter easily. The team is working to improve the manufacturing process and is working on a cradle and app for other phones, such as those running Android OS. The team hopes to begin making the cradles available by next year.

The group is also working with other groups across the I of U campus to explore other uses for the iPhone biosensor. Cunningham and his colleagues received a grant from the NSF to expand the research and range of experiments that can be performed with the software and smartphone.

The team is working closely with Steven Lumetta, a professor of electrical and computer engineering and of computer science at the U of I and food science and human nutrition professor Juan Andrade to further develop the biosensor technology.

“It´s our goal to expand the range of biological experiments that can be performed with a phone and its camera being used as a spectrometer,” Cunningham said. “In our first paper, we showed the ability to use a photonic crystal biosensor, but in our NSF grant, we´re creating a multi-mode biosensor. We´ll use the phone and one cradle to perform four of the most widely used biosensing assays that are available.”